In light illumination applications, especially in digital projectors requiring high brightness such as in cinema applications, arc lamps capable of generating an output of 10,000 lumens or more are still considered to be the most cost effective light source. Laser is an alternative light source, but requires substantial price premium. Another possible alternative light source is a light emitting diode (LED) which can be an ideal candidate because the lifetime of more than 20,000 hours is several orders of magnitude greater than that of arc lamps, thereby resulting in lower operating cost.
However, one disadvantage of an LED is its low brightness compared to the arc lamps. An LED chip, for example, may produce an output of less than 1,000 lumens. Thus, there is a need to provide an improved LED based light illumination system that has higher light output.